Oghma Infinium that is in your inventory and not read is necessary for this glitch (obtained from the daedric quest 'Discerning the Transmundane'), as well as a book shelf (found in breezehome after getting the alchemy lab upgrade). Save before going further. Go to the book shelf and read the book, then select your skill set.Close the book but do not exit the bookshelf. Store the book into the bookshelf and then exit it. Take the book off the shelf and select the option (Do not read). Repeat the process until desired.
Whenever get to a point when you're climbing a mountain off set paths and you can't progress forward any longer because the grade is too steep, simply face backwards and start jumping. Just point your butt toward the peak and continually hit the jump button. Also try moving slightly from side-to-side as you try this. You can often snag a rock along the way and shimmy up a mountain without having to use a set path. Sometimes facing forward at a 45-degree angle helps, as well.
In Embershed mine (the first you encounter after leaving Helgen), take all the torches off of their mounts and leave. When you re-enter the mine, the torches will have been replaced. Stock up and keep them in your house for easy access.
At random moments in the game, the shopkeepers of Whiterun (and possibly elsewhere) will sell a "Miscellaneous" item called "Do Not Delete". It appears to be a common treasure chest. However, much like the paintbrushes in Oblivion, they have no laws of gravity applied to them. When you drop them, they float wherever your cursor was. Buy two of them to get into areas you couldn't reach before, or (if you have the time) create a stairway to the sky.
Head to the village named "Riverwood" and find a house called "Alvor & Sigrid's House". Inside is a man named Hadvar. Rest until it is after 8 a.m. so that Alvor leaves the house. Sigrid and the young girl should remain downstairs and Hadvar will be upstairs. If he is not, wait and he will come upstairs. Save the game before the next part in case something goes wrong. Equip your best sword or weapon that you want improved skill for, and sneak behind him until he cannot see you. Do a heavy strike and he will stumble to the floor. When he gets up will have no knowledge that you hit him. He also never dies, so it can be done infinitely. Repeat the process to level up as much as desired. This will also maximize your Sneak skill, and whatever weapon type you are using.
Note: The Bound Sword spell is recommended when trying this since you are able to conjure two of these at the same time and thus gain experience faster. This works best when there is an enemy attempting to fight you, but you are at an area that they cannot reach you (for example, fighting a troll or bear while you are too high for them to actually hit you). Use the Bound Sword spell, put the sword(s) away, then repeat the process. Doing this will increase your conjuration levels very quickly.
For this trick you must have dragons roaming around and being far enough in the Dark Brotherhood to have Shadowmere. When you find the location of a dragon, Fast Travel there so Shadowmere can be with you. Start the battle with the dragon. Do not worry when the dragon goes after Shadowmere, as Shadowmere is invincible and will fight and eventually will kill the dragon for you. Use the Bound Swords spell as described above and it will have the same outcome.
Using the armor stand in your house in Solitude, place any piece of apparel on the mannequin and quickly take it back before exiting the menu. Leave your house and then go back in. The armor should appear on the mannequin and will still be in your inventory.
The bookeshelves are broken but you can still use anything you can store the book in. You do NOT have to close the container either. First, open the chest (above bookshelf in whiterun for example) or any container you can store items in. Then, read the book in your inventory. Now select a path and hit B then store the book. Scroll up to the "Chest" area and take the book (skips the (Do Not Read) part and the book does not open). Now repeat this all. This has been tested and confirmed.
Head to Falkreath and locate the smith called Lod. He will ask you to find his dog. You can find the dog Barbas outside of the village and it will take you to the Shrine of Clavicus Vile. After speaking with the Daedra Lord, the dog will accompany you until you complete the A Daedra's Best Friend quest. The dog is technically a quest item and thus can't be destroyed. It will automatically attack enemies who approach you and, since he can't lose any health, he is the best tank ever. Note: You may take another companion in addition to the dog.
At the start of the game when you get to the first town of Riverwood, start chopping wood and find the man named Hod. He normally stands at the top of the sawmill during the day. He will pay you for "all the wood you can carry" as he puts it. However, there is no limit to how much you can make by chopping wood and selling it to him. He never runs out of gold like the merchants. Chop and sell wood to him until you have tons of gold.
Note: A Soul Trap weapon and access to a smithy and arcane enchanter are required. First, buy equal amounts of Iron Ingots, Leather Strips and Petty Soul Gems. Fill the Petty Soul Gems (by killing with the Soul Trap weapon), then go to a smithy. Create as many Iron Daggers as possible, then go to an arcane enchanter (there is one in Dragonsreach). Enchant all the daggers with the Petty Soul Gems (disenchant the Soul Trap weapon if reqiored), then go to a shop and sell the daggers. Depending on your barter skill, you will get about 170 gold per dagger in profit, and should level up quite a bit. Note: Smithy every three or four daggers; enchant every one or two daggers early on.
At Solitude, go to the imperial legion headquarters. Go to the courtyard where there are several soldiers shooting arrows at targets. You can take the arrows from the targets and the men will continually shoot at the targets. They never run out of arrows. This is a way to get unlimited steel arrows and money because you can sell the arrows.
While walking around guards there is a chance they will say "Let me guess, someone stole your Sweet Roll?", a reference to the start of Fallout 3 where you have your birthday sweet roll stolen from you by Butch.
At the throat of the world, climb to the very top of the mountain (even higher than the word wall at the peak) to find a unique pickaxe named "Notched Pickaxe" This is a reference to the popular indie game "Minecraft" and its creator "Notch", which is extra funny considering the recent legal battle between Bethesda Softworks and Notch's Company: Mojang.
Equip the Rusty Mace and click on any weapon mount in Hjerlim to remove the mace from your inventory even though it is a quest item. Complete the quest and receive the mace with unlocked potential, the Mace of Molag Bal. This can be used to keep other quest weapons that you are meant to give to others. Since the game assumes it is impossible that the item is not in you inventory, quests proceed as normal though you have kept the weapons for yourself.
Go to Faendal at riverwood, the wood elf that usually stands by the mill. Ask him to follow you, then ask him to train your archery. (Have some gold around at least to make your first purchase of training). Ask to borrow something and take his gold; it's not considered stealing. Now repeat this for plenty of skill. Note: You can only level archery 5 times per level, but you level up a bit every time your archery skill goes up. This will work with any trainer who can also be a follower.
After reaching Riverwood, speak to the bartender inside the inn. Ask him if he has heard any rumors. He will eventually tell you about a boy that wants to summon the Dark Brotherhood. Follow the subquest to Windhelm. When entering Windhelm, make a sharp right and travel up the path until you encounter a Dark Elf and child talking. Enter the door to their left and find the child inside. He will ask you to kill Grinelda The Kind in Riften. Go to Riften, enter the orphanage, and murder Grinelda. Fast Travel back to Windhelm and talk to the child again to get your reward. Next, go outside of the city and wait for twenty four hours. A courier will approach and give you a note with a black handprint on it, with the words "We Know". Go to the nearest inn, rent a room, and sleep for twenty four hours. When you awake you will have been kidnapped by one of the Dark Brotherhood. They will tell you that if you kill one of the other three people in the room they will release you. Pick a person and kill them. Speak to the Dark Brotherhood again and they will tell you to meet them at their lair in the pine forest in the far southwest corner of Skyrim. Fast Travel to the western watchtower outside of Whiterun then travel west towards the marker. When you get to the door, answer the question asked with "Silence, My Brother" to enter the sanctuary. Speak to the first person you find inside the lair, and you are now part of the Dark Brotherhood.
Inside the cave during your first mission for Dragonreach, you must solve a combination puzzle. Look to the wall above the closed gate and notice two heads with a gap in the middle. Each one holds a picture of a creature (snake and dolphin). On the floor by the lever is the third creature (snake). The combination is Snake, Snake, Dolphine. The second combination is found deeper in the chambers. It is a turntable combination, which is harder. This one is Bear, Owl, Bird. Insert the claw and the door will open.
-Look inside the museum of Dawnstar to find a display case that has a yellowing piece of paper with the symbol for Oblivion. Pick the lock and use a spell for a couple seconds on the paper to turn it into a bucket.
-Once you join up with the Dark Brotherhood, you will eventually encounter a fellow named Cicero. After he gets settled into the sanctuary you can enter his room. There you will find a series of journals, and inside one of the journals Cicero talks of once upon a time killing the "Arena Champion" by posing as a crazed fan and leading him to the woods to kill him, a possible reference to "The Adoring Fan" of TES: Oblivion.
In Dawnstar, a bit left of the entrance to Iron-Breaker Mine, are a tree and three rocks. Move toward the rock in the back and look down at it to receive a prompt to open a chest. Do so and you will find plenty of equipment (both enchanted and standard), gold, crafting consumables and potions. These items will improve in quality as your level increases. The chest is tied to the salable inventory of the Khajit Ahkari. Ahkari wanders Skyrim with her caravan but can be easily found outside Dawnstar. If you Fast Travel to Dawnstar, she will be in the tent right behind you. If you do not see the group, Wait (by pressing SELECT/BACK and waiting in-game hours) until she is there. There are two ways to respawn the chest; if you wait 48 in-game hours, her inventory will restock, restocking the chest's contents as well. Alternately, you can save the game next to Ahkari, then kill her. Reload the save you just made and view her inventory. It will have restocked along with the chest's contents!
Head into the castle and find Proventus Avenicci. For this glitch to work, you need to make sure he's near something you can store items in. (his bedroom has a wardrobe that's perfect for this glitch). Also make sure you have 5000 gold and speak to him about purchasing the house. Select the answer "I'll take it" and immediately press "O" to back out of the conversation, then immediately open up the wardrobe and store all your gold in it. You'll receive the key to the house, and then you can retrieve all your gold from the wardrobe.
Whenever you go to a forge, speak to the person in charge of it and purchase all the iron ingot and leather or leather strips they are selling. After that, make as many leather strips as it takes for each iron ingot. Take it to the forge and make an iron dagger that only takes one of each ingredient to create. If you sell it back to the merchant, sell it one at a time so you create more transactions to level up the Speech skill.
At the start in Helgen's Keep, you will encounter a sleeping bear. Your guide says that you can either sneak past it or kill it. Just off to the left of where your guide stops is a small rock pile. Go to the back side of it, and you can sneak in the crevice there and stay hidden from the bear. Continue sneaking at the rock and your skill will increase. You can do this for as desired, because the bear only moves if it detects you. To make sure you are in a good location, sneak for a short time, then check your Sneak skill to see if it is rising. If not, move slightly closer to the bear and keep trying.
Prior to completing the first quest for the jarl of Whiterun (giving the dragonstone to the wizard), the world will be void of Dragons. Take this opportunity to go out and grab a couple advanced shouts or items from areas too difficult to reach due to dragons.
Locate Ungrien in Rifton and tell him "Tell Me about Maven Black-Briar." Select the persuasion option (requires 25 Speech or higher). If successful, the option doesn't go away and you repeatedly use it until you hit 100 in speech.